Bill McCarthy wrote:
Hello Vim List,
First I should mention that I'm using Windows and a native
compiler (MinGW). Meta (M) and Alt (A) are exchangeable in
Windows - I use Alt (A) below.
For each function key, Vim should give me as many as 8 maps
per key. All testing was done in normal mode. To check
this, the following script was used:
map <f7> :echo "F7"<CR>
map <a-f7> :echo "A-F7"<CR>
map <c-f7> :echo "C-F7"<CR>
map <s-f7> :echo "S-F7"<CR>
map <a-c-f7> :echo "A-C-F7"<CR>
map <a-s-f7> :echo "A-S-F7"<CR>
map <c-s-f7> :echo "C-S-F7"<CR>
map <a-c-s-f7> :echo "A-C-S-F7"<CR>
The output of :map is:
<M-C-S-F7> :echo "A-C-S-F7"<CR>
<C-S-F7> :echo "C-S-F7"<CR>
<M-S-F7> :echo "A-S-F7"<CR>
<M-C-F7> :echo "A-C-F7"<CR>
<C-F7> :echo "C-F7"<CR>
<M-F7> :echo "A-F7"<CR>
<S-F7> :echo "S-F7"<CR>
<F7> :echo "F7"<CR>
All 8 work fine. I tried this with special key <Home>
and that also worked fine for all 8 variants.
Next I tried the letter z. I used the same script as for
testing <F7> but substituting f7 with z and replacing "map
<f7>" with "map z". The output of :map is:
<C-Z> :echo "C-S-z"<CR>
Z :echo "S-z"<CR>
z :echo "z"<CR>
š :echo "A-C-S-z"<CR>
Ú :echo "A-S-z"<CR>
ú :echo "A-z"<CR>
Only 6 maps appear. The <C-z> and <C-S-z> override each
other - they are not case sensitive. No matter which way
they are defined, executing the map with either <C-z> or
<C-Z> works fine. I'm comfortable with this behavior.
The <A-C-z> and <A-C-S-z> also override each other. However
the most recent define does not work. It seems strange that
mapping the normal keyboard cannot be done with an Alt-Ctrl.
So although 6 maps appear in :map, only 5 actually work.
Finally, I tried comma. The output of :map is:
, :echo ","<CR>
<C-S-¬> :echo "A-C-S-,"<CR>
<C-S-,> :echo "C-S-,"<CR>
<S-¬> :echo "A-S-,"<CR>
<C-¬> :echo "A-C-,"<CR>
<S-,> :echo "S-,"<CR>
<C-,> :echo "C-,"<CR>
¬ :echo "A-,"<CR>
All 8 appear, however only 2 work. The working maps are for
"," and "A-,". I expected <S-,> to map the '<' key. I'm
surprised that <C-,> doesn't work - is it that way on 'nix
systems?
Should Vim store the 1 non-working map for z and the 6
non-working maps for comma?
Also, why doesn't <A-C-key> work for normal keyboard
characters?
Finally, why use these strange decorated characters for maps
containing an Alt? These make the output of :map (and
relatives) useless for those mappings.
"Ctrl+printable key" is not portably defined for other than the following:
Ctrl-? 127 0x7F
Ctrl-@ 0 0x00 NUL
Ctrl-A 1 0x01 also Ctrl-a
Ctrl-B 2 0x02 also Ctrl-b
Ctrl-C 3 0x03 also Ctrl-c
Ctrl-D 4 0x04 also Ctrl-d
Ctrl-E 5 0x05 also Ctrl-e
Ctrl-F 6 0x06 also Ctrl-f
Ctrl-G 7 0x07 BEL also Ctrl-g
Ctrl-H 8 0x08 BS also Ctrl-h
Ctrl-I 9 0x09 HT also Ctrl-i
Ctrl-J 10 0x0A LF also Ctrl-j
Ctrl-K 11 0x0B also Ctrl-k
Ctrl-L 12 0x0C FF also Ctrl-l
Ctrl-M 13 0x0D CR also Ctrl-m
Ctrl-N 14 0x0E also Ctrl-n
Ctrl-O 15 0x0F also Ctrl-o
Ctrl-P 16 0x10 also Ctrl-p
Ctrl-Q 17 0x11 also Ctrl-q
Ctrl-R 18 0x12 also Ctrl-r
Ctrl-S 19 0x13 also Ctrl-s
Ctrl-T 20 0x14 also Ctrl-t
Ctrl-U 21 0x15 also Ctrl-u
Ctrl-V 22 0x16 also Ctrl-v
Ctrl-W 23 0x17 also Ctrl-w
Ctrl-X 24 0x18 also Ctrl-x
Ctrl-Y 25 0x19 also Ctrl-y
Ctrl-Z 26 0x1A also Ctrl-z
Ctrl-[ 27 0x1B ESC
Ctrl-\ 28 0x1C
Ctrl-] 29 0x1D
Ctrl-^ 30 0x1E
Ctrl-_ 31 0x1F
The above (which date back to the time of 8-bit computers, the first of which
had only printable keys plus Shift and Ctrl; maybe even to the time of 7-bit
teletypewriters) explain why Vim sees Tab and Ctrl-I, Enter and Ctrl-M, Esc
and Ctrl-[ as pairs of synonyms.
Alt+printable key is usually translated by (key OR 0x80). Also Alt+ control
keys above. This explains your "decorated characters": for instance, since z
is 0x7A, Alt-z is mapped as 0xFA which (in Latin1 encoding) is ú (small u with
acute accent). Similarly, Alt-space should map to 0xA0, the non-breaking space
character known to HTML writers as This also means that Alt+printable
key should not be used for Insert-mode mappings because they collide with
accented characters which one may want to be able to input directly.
Non-printable keys generate (with a few exceptions like Esc, Tab and Enter)
more than one byte of keyboard data; and Alt and/or Ctrl and/or Shift
combinations (with non-printable keys) are mapped separately. The translations
(which vary between terminal models) rely on the termcap/terminfo libraries
(see ":help startup-terminal"). For instance, gvim uses "builtin_gui", a
builtin entry (precompiled into gvim), and console Vim may use "linux",
"xterm", "vt100" (which are common on Unix/Linux systems), "pcterm", "win32"
(which are common on Dos/Windows systems) or something else depending on the
particular console terminal it is using. The current terminal type is stored
in the 'term' option (which cannot be changed in gvim). ":set termcap"
displays the currently known terminal settings (which include the key bindings
in console Vim but not in gvim): what it displays is basically a dump of the
termcap entry currently in use.
Depending on the underlying OS and window manager, some key combinations can
be preempted by the window manager, and never reach Vim. For instance, on my
Linux system with kwm window manager, Alt-Fn triggers a system menu or action,
Ctrl-Alt-Fn selects a virtual console ({1..12} are defined and {1..7,10} are
actually used) and Ctrl-Fn selects a virtual desktop (the number of such
virtual desktops is user-defined; I have 20 so all 12 Ctrl-Fn keys are taken).
Thus I can use Fn and Shift-Fn in gvim but not Ctrl-Fn, Alt-Fn or Ctrl-Alt-Fn
because the latter three kinds never reach any program running in X11.
HTH,
Tony.
